1. Field of the Invention
This invention relates to the field of radio receiver and transmitter calibration and testing equipment and, more particularly, to an apparatus and a method for testing police band radar detectors that are capable of detecting microwave transmitters of the type used for automobile speed measurement.
2. Description of the Prior Art
Heretofore, there has not been a reliable and practical performance verification method or apparatus for testing a police radar detecting device.
The following prior art publications deal with the technology of radar detection: an article entitled "Eight Triband Radar Detectors" in Car Audio Magazine, March 1991, Vol. 4, No. 3, pages 92-103; an article entitled "Radar Detector Tester" in Radio Electronics, February 1990, Vol. 61, No. 2, pages 37-38; Owner's Manual, Passport Radar Receiver, 1989, by Cincinnati Microwave, Inc., pages 32-33; Owner's Manual, Bel Vector Radar Detector by Bel-Tronics Ltd. (copyright unknown); an article entitled "Radar Speed-Gun Controller" in Radio Electronics, August 1986, Vol. 57, No. 8, pages 39-42 and 85; and an article entitled "Radar Signal Detector" in Radio Electronics, July 1986, Vol. 57, No. 7, pages 52, 97.
The article entitled "Eight Triband Radar Detectors" in Car Audio Magazine evaluates the performance of several radar detectors on the X, K, and Ka bands utilizing police speed measurement equipment. This method, which employs a police radar gun, is impractical and prohibitively expensive for routine testing of radar detectors. The article states that radar detector malfunction is not an unusual occurrence. Thus, the need for a reliable method and apparatus to verify radar detector performance is underscored.
The article entitled "Radar Detector Tester" in Radio Electronics provides a method and apparatus for comparing radar receiving sensitivity between two radar detectors. This method and apparatus, however, is used to determine a relative sensitivity. Furthermore, it is believed, apparently due to signal strength, that the operator must leave the automobile in order to effect a change in the field strength meter of the radar detector. Thus, performance verification may not be implemented while the radar detector is in use. It is also believed that this apparatus would transmit at power levels in violation of present U.S. regulatory laws and policies.
The Passport Radar Receiver in the Owner's Manual provides a method that includes an averaging technique of false signals. This method, however, requires the presence of routinely encountered false signals on a regular route and is claimed to be a semi-reliable method by this reference. Additionally, this method will not test the performance of signals used exclusively for police band radar.
The article entitled "Radar Speed-Gun Controller" in Radio Electronics provides an apparatus for testing and calibrating speed measurement equipment in the laboratory. The apparatus, also known as a radar jammer, interferes with police radar and, therefore, is in violation of present U.S. regulatory laws and policies.
The article entitled "Radar Signal Detector" in Radio Electronics provides an apparatus to test a radar signal detector by the generation of a non-specific broadband radio frequency signal. An RF signal, such as that derived from the cited apparatus, is also believed to be in violation of present U.S. regulatory laws and policies.
The Bel Vector Owner's Manual by Bel-Tronics Ltd. provides an imprecise method to test radar detectors that includes the use of false signals as a performance indicator.
The present invention is particularly suited for an individual who is untrained in the field of electronics for the purpose of performing a simple, rapid and accurate test to determine whether radar detection equipment is functioning. By the present invention, the performance of the radar detector is tested by using a single apparatus. The apparatus uses the minimal amount of radio frequency (R.F.) power output that is necessary to accomplish the task. In addition, the radar detector can be tested while the radar detector is in use.
Further, the present apparatus transmits at three different frequencies so that all police radar band reception of the radar detector can be tested.
None of the above citations achieves or fulfills the purposes of the apparatus and method of the present invention.